Electrical steering system for boats

ABSTRACT

There is disclosed a control system for electronically controlling a boat powered by a conventional twin screw inboardoutboard drive system. The boat is maneuvered by a plurality of reversible direct current motors which are controlled through a complex electronic circuit system by a portable control box. The portable control box is disengageably connected to the electronic system so that the boat may be maneuvered from any position thereon.

O ilnrted States Patent 1 1 1111 3,865,063

Norton 1 Feb. 11, 1975 ELECTRICAL STEERING SYSTEM FOR 2,248,564 7/1941Wood 192/142 R BOATS 2,323,619 7/1943 Punish 192/84 R 3,051,886 8/1962Cadwallader 114/144 R X [75] Inventor: Calhoun Norton, Tequesta, Fla.

[73] Assignee: Arens Controls, Inc., Evanston, 111. Primary ExaminerGeorge E. Halvosa [22] Filed; 3 973 Assistant ExaminerStephen G. KuninAttorney, Agent, or FirmOlson, Trexler, Wolters, 1211 PP' lo-14241290Bushnell & Fosse, Ltd.

Related US. Application Data [62] Division of Ser. No. 201,708, Nov. 24,1971,

abandoned, which is a division of Ser. No. 25,874, ABSTRACT April 6,1970, Pat. No. 3,651,779.

There 1s dlsclosed a control system for electronically 52 U.S. c1.114/144 R, 74/335, 74/480 B, Controlling a boat powered y a conventionaltwin 1 14/157 115/35 192/093 31 /5 screw inboard-outboard drive system.The boat is ma- 51 Int. Cl B63h 25/24 neuvered by a plurality ofreversible direct current [58] Field of Search 74/335, 480 B; 114/144 R,motors which are controlled through a complex elec- 4 57; 115 R, 18 E 3537; 1 0 791; tronic circuit system by a portable control box. The 92 0909 432 51 34 R, 142 31 /5 portable control box is disengageablyconnected to the electronic system so that the boat may be maneuvered 5References Cited from any position thereon.

NI ED TA E PATENTS l 859 493 U T S T S 3 Claims, 6 Drawing Figures5/1932 Bernady 192/142 R T0 THROTTLE LEVER 68 PATENTEU FEB] 1 ms sum 10F3 PATENTEDFEBI 1 1915' SHEET 2 OF 3 swrrcm e clRcU/r OPERA 770 AMP-(IIRCO/ r Ad INPUT CIRCl IT PATENI FEB I ma SHEET 30F 3 JE'LIQF 1ELECTRICAL STEERING SYSTEM FOR BOATS This is a Divisional Application ofSer. No. 201,708 filed Nov. 24, 1971 now abandoned which, in turn, was aDivisional Application of Ser. No. 25,874 filed Apr. 6, I970 now U.S.Pat. No. 3,651,779.

This invention relates generally to a control system for maneuvering aboat, and more particularly to an electronic control system formaneuvering a boat.

In the past, steering arrangements for boats were disclosed inaccordance with my own U.S. Pat. No. 3,294,054 which shows amechanically coupled steering system without the use of electroniccontrols. Although the system therein disclosed provides an excellentsteering mechanism for facilitating maneuvering of the boat, it has beenfound that by utilizing an electronic control system, as disclosedhereinafter, the ability to maneuver a boat is enhanced. It has alsobeen found that boat maneuverability can be controlled from any positionon the boat whereas such a feat is not possible by utilizing amechanically coupled system by itself.

Accordingly, a general object of the present invention is to provide anovel electronic control system for maneuvering a boat.

Another object of the present invention is to provide an electroniccontrol system for maneuvering a boat wherein maneuvering can beaccomplished from any desired position.

A more specific object of the present invention is to provide anelectronic control system for controlling the maneuverability of a boatwherein the clutch, throttle, and steering mechanism of the drive systemcan be independently regulated from various remote positions.

A further object of the present invention is to provide novel electroniccontrol circuits for the control of the clutch, throttle and steeringmechanisms ofa boat drive system.

Other objects and advantages of the present inven tion will becomeapparent from the following description taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a block diagram of the electronic control system forcontrolling the maneuverability of a boat powered by a twin screwinboard--outboard drive system;

FIG. 2 is a block diagram of the electronic control circuit forcontrolling the throttles and steering of the boat;

FIG. 3 is a schematic diagram of the electronic control circuit forcontrolling the steering of the boat;

FIG. 4 is a schematic diagram of the direct current reversible motorsused in conjunction with the electronic control circuit of FIG. 3 forcontrolling the steering of the boat;

FIG. 5 is a schematic diagram of the electronic control circuit anddirect current reversible motor for controlling the throttles of theboat; and,

FIG. 6 is a schematic diagram of the electronic control circuit anddirect current reversible motor for controlling the clutch mechanisms ofthe boat.

Referring now more specifically to the drawings and particularly to FIG.1, the rear end section of a boat 10 is shown, conventionally powered bya twin screw inboard--outboard drive system designated generally by thenumerals 12 and 14 although it is to be understood that conventionaloutboard engines could also be used. An electronic control systemdesignated generally by the numeral 16 electronically controls themaneuverability of the boat 10 in the same manner as the boat disclosedin my U.S. Pat. No. 3,294,054, is maneuvered but with a higher degree ofaccuracy. For a discussion of the particular maneuvering positions andthe various forces required for these respective positions. reference ismade to the above mentioned-patent.

The inboard--outboard drive system 12 is positioned on the left or portside of the boat and includes an engine 18 mounted within the boatproviding the power for a port outboard drive unit 20 conventionallymounted on the boat transom at the rear or stem of the boat. A movablethrottle arm 21 co-operates with the engine 18 for varying the poweroutput of the engine from no power or idle power when the throttle armis in the position as indicated in solid lines to full power when thethrottle arm is positioned as indicated in dotted lines.

The outboard drive unit 20 includes a propeller 22 mounted on the end ofa propeller shaft (not shown) which extends in a generally horizontalposition rearwardly with respect to the boat transom. A tiller orsteering lever 24 is provided for swinging the drive unit to the left orright about a generally vertical pivot 26, as viewed in FIG. 1, tochange the angle of thrust of the propeller with respect to alongitudinal axis 28 of the boat. The extreme positions, both leftand-right. of the outboard drive unit 20 are indicated by dotted linesin FIG. 1. An engageable clutch member 30 is provided for engaging anddisengaging the engine 18 and outboard drive unit 20. As indicated inFIG. 1, the clutch can be positioned to the far left for engaging theengine and outboard drive unit wherein the propeller 22 is driven in onedirection for providing forward power to the boat 10. The propeller isdriven in an opposite direction for providing rearward power to the boat10 by positioning the clutch member 30 to the far right and finally,positioning the clutch intermediate the two about described extremepositions disengages the motor and drive unit.

The inboard-outboard drive system 14 is positioned on the right orstarboard side of the boat and includes an engine 18a mounted within theboat providing the power for a starboard outboard drive unit 20a mountedon the boat transom at the rear or stern of the boat. Theinboard--outboard drive system 14 is structurally and functionallyexactly the same as the inboard-outboard drive system 12 and thereforelike components are designated with like numbers with an additionalsuffix a indicating the components of the drive system 14.

The maneuverability of the boat 10 is dependent upon three factors,firstly, the physical positioning of the propellers 22 and 220 withrespect to the longitudinal axis 28 of the boat, secondly, the amount ofpower delivered by the engines 18 and 18a which is determined by thepositions of throttle arms 21 and 21a, and thirdly, by the directionpropellers 22'and 22a are driven which is dependent upon whether theclutches 30 and 30a engage their respective engine and drive unit in aforward or reverse manner. As stated above, reference can be made to myU.S. Pat. No. 3,294,054, for a detailed description of the variousmaneuvering positions utilizing these factors.

For each inboard--outboard drive system 12 and 14, the electroniccontrol system 16 provides a steering motor assembly 32 and 32arespectively, a throttle motor assembly 34 and 34a respectively, and aclutch motor assembly 36 and 36a respectively. The steering motorassemblies 32 and 32a control the positioning of their respective driveunits 20 and 20a as described in more detail hereinafter. The throttlemotor assemblies 34 and 34a are used to position their respectivethrottle arms 21 and 21a for controlling the power output of theirrespective engines 18 and 18a and the clutch motor assemblies 36 and 36aare provided for positioning their respective clutch members 30 and 30afor controlling the engaging status of their respective engine andoutboard drive units.

The electronic control 16 also includes electronic control circuitry,described in detail hereinafter, positioned within a control panel 38which may be mounted on boat in any convenient location. The controlcircuitry is electrically connected to the above described motorassemblies via conduits 40 for controlling the motor assemblies asdescribed below. Additional electronic control circuitry co-operatingwith the circuitry within control panel 38 is located within a portablecontrol box 42. The control circuitry within the control box may bedisengageably connected to the control circuitry within control panel 38for cooperating therewith. This is accomplished by an electrical cordand plug 44 which co-operates with a socket 46 for connecting anddisconnecting the electronic circuitry in control panel 38 and portablecontrol box 42. This disengageable feature allows the operator of boat10 to maneuver the boat from any position thereon merely by supplying anappropriate extension cord (not shown) or if desired by providingadditional sockets located in various positions on the boat andconnecting the electronic circuitry within control panel 38 to thosesockets.

The steering motor assembly 32 includes a reversible direct currentmotor 48 and a piston assembly 50 mechanically coupled to the output ofreversible motor 48 for driving a piston or actuator 52 of the pistonassembly 50. The piston 52 is driven from a retracted position asindicated by solid lines in FIG. 1 to an extended position as indicatedin dotted lines when the reversible motor 48 is forwardly driven andback to its retracted position when the reversible motor is reverselydriven. It is to be understood that the reversible direct current motorand the piston assembly are both conventional and conventionally coupledto each other so as to provide the above described results and thereforewill not be discussed in further detail. The free end of piston 52 whichmay be a gear driven rack is mechanically connected to the steeringlever 24 of the port outboard drive unit by means not shown so as todrive the outboard drive unit and corresponding propeller 22 from theextreme right as viewed in FIG. 1 when the piston is in its extendedposition to the extreme left when the piston is in its retractedposition.

A steering motor assembly 32a which is both structurally andfunctionally identical to the steering motor assembly 32 is mechanicallycoupled to the steering lever 24a of the starboard outboard drive unit20a in the same manner as steering motor assembly 32 is coupled tosteering lever 24. The reversible direct current motor, piston assembly,and actuator of the steering motor assembly 320 are designated bynumerals 48a, 50a, and 52a respectively. It is to be noted that when theactuator 52a is in its extended position as indicated by dotted lines,the starboard outboard drive unit 20a and its corresponding propeller22a are positioned to the right as viewed in FIG. 1. This is identicalas that described with respect to port outboard drive unit 20. It is tobe understood that the piston 52a may be easily coupled to the steeringlever 24a in such a manner so as to have the propeller 22a positioned tothe left when the piston is in its extended position.

The throttle motor assemblies 34 and 34a are likewise structurally andfunctionally equivalent to the steering motor assembly 32, thereversible direct current motor, piston assembly, and actuator ofthrottle motor assembly 34 being designated by numerals 54, 56 and 58respectively while the reversible direct current motor, piston assembly,and actuator of the throttle motor assembly 34a being designated bynumerals 54a, 56a and 58a respectively. The free end of piston 58 orrack is mechanically connected to the throttle arm 21 of engine 18 so asto drive the throttle arm 21 from its position as indicated in solidlines when the actuator is in its retracted position to a positionasindicated in dotted lines when the actuator is in its extendedposition. As stated above, when the throttle arm is in its solid linedposition, the engine 18 merely provides idle power and when the throttlearm is in its dotted lined position, the engine provides full power. Itis to be understood that the engine power continuously increases as thethrottle arm is driven from its solid lined position to its dotted linedposition. The actuator 58a is mechanically coupled to the throttle arm21a in the same manner for controlling the power output of engine 18a.

The clutch motor assemblies 36 and 36a are also both structurally andfunctionally identical to steering motor assembly 32 and includerespective reversible direct current motors 60 and 60a, piston or rackassemblies 62 and 62a, and actuators 64 and 64a. The free end ofactuator 64 is mechanically connected to the engageable clutch member 30for driving the clutch member from its far left position, as viewed inFIG. 1, when the actuator is in its retracted position to the far rightwhen theactuator is in its extended position and in an intermediateposition when the end of the actuator is intermediate its retracted andextended positions. As stated above these three clutch positionsrepresent forward engagement of the outboard drive unit 20 and enginel8, reverse engagement, and disengagement. The actuator 64a ismechanically coupled to the engageable clutch member 30a so as toprovide the same function with respect to the inboard--outboard drivesystem 14 as actuator 64 provides with respect to inboard-- -outboarddrive system 12.

Now that a sufficient description has been given of each componentrequired for maneuvering boat 10 attention is directed to portablecontrol box 42 for a discussion dealing with the control of each of theabove described components for electronically controlling themaneuverability of boat 10. It is to be understood that each individualcontrol mechanism on portable control box 42 is appropriately connectedto the electronic circuitry required to control the various componentsas described above and that this electronic circuitry will be describedin great detail subsequently.

The portable control box includes a steering wheel 66 and a switch 67which may be referred to as a maneuvering switch. This switch is a2-position switch, one position being the cruise" position and the otherposition being the maneuvering position. The steering wheel 66 isappropriately coupled to the electronic circuitry so as to drive thepistons 52 and 52a of steering motor assemblies 32 and 32a respectivelywhen the steering wheel is turned either clockwise or counterclockwiseas viewed in FIG. I. This, of course, causes the outboard drive units 20and 20a respectively to pivot about vertical pivots 26 and 26a.

When the maneuvering switch 68 is in the cruise position, the electroniccircuitry is such that the outboard drive units 20 and 20a arepositioned parallel to each other and remain parallel to each other whenthe steering wheel is turned. That is to say, for example, when thesteering wheel is turned clockwise the outboard drive units willconcurrrently pivot to the right as viewed in FIG. 1 and will pivot tothe left when the steering wheel is turned counterclockwise.

When the maneuvering switch is flipped into the maneuvering position, aportion of the electronic circuitry is reversed as will be describedhereinafter. As a result, when the wheel is turned clockwise both of theoutboard drive units toe in, i.e., concurrently pivot towardseach other,and will toe in until they reach the maximum position which is about 45to the longitudinal axis 28 of the boat or at about 90 with respect toeach other. This will also be the position at which the steering wheelcan no longer be turned clockwise. When the steering wheel is turnedcounterclockwise until it can no longer be so turned, the outboard driveunits will toe out, i.e., concurrently pivot away from each other untilthey reach their stop positions which again are at about 45 angles tothe longitudinal axis 28 and at about 90 with respect to each other.

The portable control box 42 also provides a pair of throttle levers 68and 68a which are appropriately connected to the electronic circuitryfor driving throttle arms 21 and 21a respectively when the throttlelevers are moved in a forward and rearward direction. Two clutch levers70 and 70a are also provided, appropriately connected to the electroniccircuitry, for driving engageable clutch members 30 and 30a respectivelyinto positions described above when the clutch levers are moved inupward and downward directions.

When the maneuvering switch is in the cruise position, the boat issteered and the throttles are actuated in the usual manner obtainingconventional but precise results. When the maneuvering switch is in themaneuvering position with the steering wheel turned clockwise as far asit can go so that both drive units are toed in, free maneuverability canbe obtained. In this condition and with both clutches engaged in theforward position, the boat can be steered merely by differentialoperation of the throttle levers 68 and 68a. In other words, if theright hand or starboard throttle 70a is advanced relative to the portthrottle 70 so that engine 18a has greater output power than engine 18,the boat will turn to the right. As stated above, this is explained andbroadly covered in US. Pat. No. 3,294,054.

When the drive units are toed in and with one engine engaged in reverseand the other in forward, and with the throttle levers actuatedgenerally uniformly, the boat will turn about its center of drag. Inother words, the boat will turn completely around within its own length.The direction of turn can be reversed by a turn of the steering wheelcompletely counterclockwise so that the drive units are toed out.

An interlock, which will be described with respect to FIG. 6, isprovided between the throttle electronic circuitry and the clutchelectronic circuitry so that the clutches cannot be shifted until thethrottles have been returned to the idle position. In addition, a timedelay electrical device is provided so that if the clut'ch switches havebeen shifted from one position to the other while the throttles areadvanced no shifting will take place even when the throttles arereturned to the idle position until after a small time delay whichpermits the engines to drop back to the correct speed before actualshifting takes place.

It is to be noted that the above described control system is adapted tobe connected with the usual steering, throttle and gear shift controlsof conventional structures.

Turning to FIG. 2, a block diagram of the electronic control circuit forcontrolling the throttles and steering of the boat is shown. Anadjustable input circuit 72 is connected across a 12 volt direct currentpower supply (not shown) for developing a variable differential signal.In the case of the electronic steering circuitry the value of thisdifferential signal is dependent upon the position of steering wheel 66of FIG. 1 while in the case of the electronic throttle circuitry thedifferential signal value is dependent upon the position of throttlelevers 68 or 68a. This differential signal is fed to an operationalamplifier circuit 74 which both regulates and amplifies the differentialsignal. The output of the operational amplifier circuit, which isconnected to a switching circuit 76, is referenced to a positive 6,volts and can swing either positive or negative from that valuedepending upon the sign of the differential input signal.

When for example, the steering wheel is turned in one direction thedifferential input signal is increased thus swinging the output of theoperational amplifier circuit positive with respect to the abovementioned referenceuWhen the steering wheel is turned in the oppositedirection, the differential input signal is decreased causing the outputof the operational amplifier circuit 74 to drop below the referencevoltage. The output of switching circuit 76 is electrically connected toa motor assembly circuit 78 which in the case of the electronic steeringcircuit includes the two reversible direct current motors 48 and 48a.When the output of the operational amplifier circuit is positive withrespect to the 6 volts reference, the switching circuit allows thereversible motors to be forwardly driven for driving the outboard driveunits 20 and 20a in one direction as described with respect to FIG. 1.When the output of operation amplifier circuit 74 is below the six voltsreference, the switching circuit allows the reversible motors to bereversely driven for driving the outboard drive units in an oppositedirection. As stated above, the switching circuit includes a maneuveringswitch which can adjust the switching circuit so as to drive thereversible direct current motors in opposite directions which causes theoutboard drive units to be either toed in or toed out as described withrespect to FIG. 1.

Separate electronic control circuitry is provided for the throttles andfunctions in the same manner as described above except that each portionof the circuitry controls only one reversible direct current motorincluded in motor assembly 78, that motor being either reversible directcurrent motor 54 or 54a. When, for example, the throttle lever 68 isrepositioned this either increases or decreases the value of thedifferential input signal depending upon which direction the throttlelever was moved. This variation in the differential input signal in turneither increases or decreases the output of the operational amplifiercircuit with respect to its output reference voltage causing theswitching circuit to allow the reversible direct current motor 54 to bedriven in one direction or the other.

Turning to FIG. 3, a schematic view of an electronic control circuit 79for steering boat is shown. The circuit includes a 12 volt directcurrent source 80, an adjustable input circuit 82 electrically connectedacross the power supply 80, an operational amplifier circuit 84electrically connected to the output of the adjustable input circuit,and a switching circuit 86 electrically connected to the output of theoperational amplifier circuit.

The adjustable input circuit82 includes a master potentiometer R5 and aslave potentiometer R6 forming a part of a bridge circuit 87 acrosspower supply 80. The adjusting arm 83 of potentiometer R5 ismechanically connected to the steering wheel 66 so as to be driven bythe steering wheel causing the voltage across R5 to vary when thesteering wheel is moved which in turn drives actuators 52 and 52a asdescribed above.

v Potentiometer R6 likewise has an adjusting arm 85 which ismechanically connected to the steering actuai jtors 52 and 52a forvarying the voltage across R6 in I? proportion to the movement of theactuators as will be described hereinafter. Two resistors R1 and R2connected in series across power supply 80 divide the 12 volts supply sothat 6 volts appear between resistors R1 and R2 and at the top ofpotentiometer R6 which has one end electrically connected intermediateresistors R1 and R2. A resistor R7 having one end electrically connectedto the other side of potentiometer R6 with the other side of R7connected to the negative side of power supply 70 is provided so thatthe range of voltage appearing across potentiometer R6 is about 3 volts.The voltage range of potentiometer R5 is also three volts or lessdepending upon the adjustment of potentiometers R3 and R4 which alsoform part of bridge circuit 87. Each of the potentiometers R3 and R4 hasa respective adjusting arm 86 and 88 electrically connected to arespective end of potentiometer R5. The potentiometers R3 and R4 areconnected in series with the otherwise free end of potentiometer R3electrically connected intermediate R1 and R6 and the otherwise free endof potentiometer R4 electrically connected through a resistor R19 to apoint intermediate resistors R7 and potentiometer R6. Potentiometers R3and R4 are used to adjust the range of travel of actuators 52 and 52awhen potentiometer R5 is moved from one extreme position to the otherwhich in turn is driven by moving steering wheel 66 as stated above. Theslave potentiometer R6 is mechanically connected to the actuator in sucha way that only about three turns of the ten turn potentiometer are usedfor full range travel of the actuator. In other words, the adjusting arm85 will only move a distance equal to three-tenths that of the entiredistance of potentiometer R6 when the actuators 52 and 52a are movedfrom one extreme position to the other as described with respect toFIG. 1. Therefore, about seven-tenths of the resistance of thepotentiometer R6 appears in the circuit as if it were a fixedresistanc'e. Resistor R19 is provided within the bridge 87 to match thisunvarying portion of potentiometer R6. A resistor R8 has one endelectrically connected to the actuating arm 85 of potentiometer R6 andits otherwise free end connected to the negative input terminal of anoperational amplifier 90 which will be described hereinafter. A resistorR9 electrically connects the adjusting arm 83 to the positive inputterminal of operational amplifier 90. The two resistors R8 and R9 areprovided so as to utilize the voltages across potentiometers R5 and R6as a differential input signal which is to be fed to the input ofoperational amplifier 90.

The operational amplifier circuit 84 includes an operational amplifier90 having negative and positive input terminals respectively designatedby numerals 1 and 2, an output terminal designated by the numeral 3 andadditional terminals designated by the numerals 4, 5, 6 and 7respectively. The operational amplifier circuit also includes anadjustable resistor R10 connected at one end to the output terminal 3 ofthe operational amplifier 90 with its otherwise free end connectedintermediate resistor R8 and negative input terminal 1. The resistor R10provides conventional negative feedback for the operational amplifier.The amplifier gain is determined approximately by the values ofresistors R8 and R10. The operational amplifier 90 is a conventional RCANo. CA 3029 type amplifier and reference is made to the RCA handbook RCALinear Integrated Circuits (technical series lC-41) for a detaileddiscussion of the amplifier. It is to be understood, of course, thatother operational amplifiers providing the same function as describedbelow may be substituted therefor. A resistor R11 and a capacitor C2connected in series, are provided to form a phase compensation networkfor the operational amplifier. This series circuit has one end connectedto terminal 4 of the operational amplifier and its otherwise free endconnected intermediate resistors R1 and R2. The terminal 5 of theoperational amplifier is connected to the otherwise free end of resistorR11 and the terminal 7 is connected to the negative side of power supply80. The output of the operational amplifier is referenced to a positivesix volts as discussed below and can swing either above or below thatvalue depending-upon the sign of the differential input signal. That isto say that the output of operational amplifier depends upon whether thevoltage across R9 is greater or less than the voltage across R8. Aresistor R18 is electrically connected at one end intermediate resistorR9 and positive input terminal 2 of the operational amplifier, theotherwise free end of resistor R18 being connected intermediateresistors R1 and R2. R18 has been included in the circuit for the sakeof completeness. In practice, it has not been used and is not essentialin this application.

The switching circuit 86 includes an NPN transistor Q1 and PNPtransistor Q2 each of which has its base connected to the output ofoperational amplifier 90 and its emitter connected to the emitter of theother transistor. The collector of transistor O1 is connected to thepositive side of the power supply through two biasing resistors R12 andR13 while the collector of 02 is connected to the negative side of powersupply 80 through biasing resistors R14 and R15. The emitters of bothtransistor Q1 and 02 are also connected intermediate resistors R1 and R2so that the emitters are maintained at 6 volts, the output referencevoltage of the operational amplifier as referred to above. A second NPNtransistor Q3 is connected across the power supply 80 with its baseconnected intermediate resistors R14 and R15, its emitter connected tothe negative side of the power supply, and its collector connected tothe positive side of the power supply through an electromagnetic relayK1. A second electromagnetic relay K3 is connected across theelectromagnetic relay K1. It is to be understood that theelectromagnetic relays herein referred to, are conventional relayshaving electromagnetic coils which when energized open or close normallyclosed or opened associated contact. When reference is made to the relayitself what is meant is the electromagnetic coil. A second PNP typetransistor O4 is also connected across the power supply 80 having itsbase connected intermediate resistors R12 and R13, its emitter connectedto the positiveside of power supply 80, and its collector connected tothe negative side of power supply 80 through an electromagnetic relayK2. A fourth electromagnetic relay K4 is connected across relay K2. Theelectromagnetic relays K1, K2, K3 and K4 are also electrically tied to awafer type switch 92 which may be actuated by maneuvering switch 67 suchthat electromagnetic relay K3 is electrically connected across K2 andthat electromagnetic relay K4 is connected across Kl for reasonsdescribed below.

The transistor Q3 has a filtering circuit connected across its collectorand emitter comprising a capacitor C4 and resistor R17 connected inseries while the transistor C4 has a filtering circuit connected acrossits collector and emitter comprising capacitor C3 and resistor R16connected in series. The electromagnetic relays K1, K2, K3 and K4 haverespective contacts K1, K2, K3 and K4 which are electrically connectedto reversible direct current motors 48 and 48a and will be describedwith respect to FIG. 4.

The electronic control circuit 79 of FIG. 3 includes a capacitor C1electrically connected across the resistors R1 and R2 so as to prevent adrain of power from supply 80 when reversible direct current motors 48and 48a are initially energized as described below. A diode D1 havingits anode connected to the positive side of the power supply 80 and itscathode connected to the remainder of the electronic circuit 79 isprovided to block the discharging of capacitor C1 by the motor load. Italso protects the circuit against accidental application of the wrongpolarity.

In operation, when the steering wheel 66 is maintained such that theoutboard drive units 20 and 20a are positioned parallel to thelongitudinal axis 28 of boat equal voltages appear across potentiometersR5 and R6 causing a differential input signal of zero to appear at theinput of operational amplifier 90. The emitters of transistors 01 and 02are therefore maintained at 6 volts reference causing the transistors tobe in a nonconductive state. This in turn prevents either of thetransistors Q3 or Q4 from being in a conductive state. As long as thetransistors Q3 and 04 remain in a nonconductive state, theelectromagnetic relays K1, K2, K3 and K4 remain in a de-energizedcondition which prevents the reversible motors 48 and 48a from drivingtheir respective outboard drive unit as will be described with respectto FIG. 4.

When, for example the steering wheel 66 is turned clockwise the voltageacross potentiometer R5 increases causing the bridged circuit 87 to beunbalanced and thus a positive differential input signal appears at theinput of operational amplifier 90. This in turn increases the output ofthe operational amplifier with respect to its 6 volts reference causingtransistor O1 to conduct. With Q1 conducting, transistor 04 is properlybiased, allowing electromagnetic relays K2 and K4 to be energized. Aswill be described with respect to FIG.

4, this causes reversible motors 48 and 48a to be simultaneously drivenin forward directions so that their respective actuators 52 and 52a moveto extended positions. The outboard drive units 20 and 200 will in turnbe pivoted to the right as viewed in FIG. 1. When the steering wheel isno longer turned, such that the voltage across potentiometer R5 ismaintained at a value greater than the voltage across potentiometer R6,the adjusting arm is repositioned by its mechanically connectedactuators 52 and 52a such that bridge circuit 87 is again balanced. Thisin turn drives the differential input signal to a value of zerocausingthe reversible motors 48 and 48a to be de-energized.

Similarly, if steering wheel 66 is turned counterclockwise reducing thevoltage across potentiometer R5 a negative differential input signalappears at the input of operational amplifier causing Q2 and O3 toconduct which in turn energizes electromagnetic relays KI and K3 causingthe reversible motors 48 and 48a to be driven such that the outboarddrive units 20 and 20a are pivoted to the left as viewed in FIG. I. Whenthe steering wheel is no longer turned, the potentiometer R6 is againrepositioned such that a differential input signal of zero appears atthe input of operational amplifier 90 causing the reversible motors tobe de-energized and stopping outboard drive units 20 and 20a.

Turning to FIG. 4, the reversible direct current motor 48 has itspositive or forward side connected to electromagnetic relay contact K2and its negative or reverse side connected to electromagnetic relaycontact Kl. When the electromagnetic relays K1 and K2 are in theirde-energized state, the contacts K1 and K2 connect reversible motor 48to ground as indicated by a solid line representation in FIG. 4. Whenthe electromagnetic relay K2 is energized, the contact K2 is moved toits dotted line position. This connects the reversible motor 48 to a 12volt direct current source such that the motor is driven-in a forwarddirection so as to function as described above. When the electromagneticrelay K1 is energized, contact K1 is moved to its dotted line positionsuch that the reversible motor 48 is driven in a reverse direction.Reversible motor 48a is electrically connected to a 12 volt DC powersupply in the same manner as reversible motor 48 such that motor 48a isdriven in a forward direction when electromagnetic relay K4 is energizedand in a reversed direction when electromagnetic relay K3 is energized.

The above discussion assumes that maneuvering switch 67 is in its cruse"position. If the switch is thrown to its maneuvering" position causingelectromagnetic relay K3 to be connected to K2 and K4 to be connected toK1 the operation will be the same except that motor 48a will be drivenin an opposite direction from that of motor 48. This in turn will causea toeing in and toeing out of drive units 20 and 20a as described withrespect to FIG. 1.

It is to be understood that reversible direct current motors 48 and 48amay utilize their own electronic control circuit 79 as described in FIG.3. In such a case, a potentiometer R5 of each circuit would bemechanically connected to the steering wheel 66 such that each of thepotentiometers actuating arms 82 would be moved equally andsimultaneously. It is to be further understood that the 12 volt directcurrent power supply 80 may be used to power the reversible motors 48and 48a in addition to the electronic circuitry of FIG. 3

rather than using separate power supplies as indicated in FIG. 4.

Turning to FIG. 5, an electronic control circuit for the throttle arm 21is shown. This circuit functionally and structurally is similar to thatcircuit disclosed with respect to FIG. 3 with exceptions indicatedbelow. Electrical components of the electronic circuitry of FIG. 5 whichare equivalent to those components of FIG. 3 are designated with likenumerals in addition to a suffix a.

The first electrical difference between the two circuits is thatpotentiometer R19 replaces resistors R19, R3 and R4. The potentiometerR19 serves to limit the range of travel of actuator 58 for a given rangeof travel of the master potentiometer R5a. As stated above, thisfunction was provided by potentiometers R3 and R4 of electronic controlcircuit 79 of FIG. 3. The actuating arm 96 of potentiometer R19 iselectrically connected to the negative side of power supply 80a throughresistor R7a. A second difference is that a zener diode D2 has beenadded, which diode is electrically connected intermediate variableresistor R10 and input terminal 1 of the operational amplifier 90.Thirdly, resistors R16 and R17 and capacitors C3 and C4 have beeneliminated along with resistor R18. Finally, electromagnetic relays K3and K4 have been eliminated so that the electronic circuit controls onlyone reversible direct current motor which as shown in FIG. 5 is thethrottle reversible motor 54.

In operation, when the throttle lever 68 is maintained in its idleposition equal voltages appear across potentiometers R5 and R6 which asin the case of electronic control circuit 70 causes transistors Q1, Q2,Q3 and O4 to be off which in turn maintains electromagnetic relays K1and K2 in their de-energized state so that reversibe motor 54 isde'energized. When the throttle lever IS forwardly moved, the voltageacross potentiometer R5 increases so that reversible motor 54 isforwardly driven causing actuator 58 to drive throttle arm 21 asidescribed with respect to FIG. 1. The motor 54 is de-energized when thevoltage across potentiometer R6 goes to a value such that thedifferential input signal appearing at the input of operationalamplifier 90 is equalto zero as in the case of circuit 79. Thereversible direct current motor 54 may be reversed in the same manner asdescribed with respect to the electronic control circuit 79.

It is to be understood that a circuit equivalent to that described withrespect to FIG. 5 is provided for the throttle arm 21a and is actuatedin the same manner by throttle lever 68a.

Turning to FIG. 6, an electronic control circuit 100 for controlling theengageable clutch member as described in FIG. 1 is connected across al2-volt direct current power supply 102. The electronic control circuit100 includes a wafer shaped switch 104 which is mechanically coupled tothe clutch actuating motor 60, of the clutch motor assembly 36 so as tofunction as described below. The wafer switch 104 has two conductiveportions 106a and 1061; each of which substantially comprises arespective half of the wafer switch. The conductive portions may be madefrom copper or like conductive material. The wafer also has two wedgeshaped insulating or nonconductive portions 108a and 108b each of whichextends from an opposite outer edge of the wafer and meets at the centerthereof. The

nonconductive portions separate the two conductive portions 106a and106b.

The electronic control circuit 100 also includes a three-position switch110 having three positions indicated by the letters F, N and Rrespectively and a movement arm indicated, by the numeral 112. The pointabout which movement arm 112 pivots is electrically connected to thenegative side of power supply 102 through a switch 114 and a timingswitch 116. The switches 114 and 116 are operably connected to thethrottle lever 68 by means not shown and function in a manner describedbelow. The F or forward position of switch 110 is slideably andelectrically connected to the wafer switch 104 by tap member 118. Thetap 118 is positioned adjacent the lower left hand quadrant of waferswitch 104 as viewed in FIG. 6 such that the tap maintains contact withthe wafer switch when the wafer switch is rotated as described below.The R or reverse position of switch 110 is connected to the lower rightquadrant of wafer switch 104 by tap member 120 in the same manner asdescribed with respect to tap member 118. The N position of switch 110is likewise slideably and electrically connected to the wafer switch 104by tap member 122. The tap member 122 is positioned on the wafer switchintermediate taps 118 and 120.

The, electronic circuit 100 also includes electromagnetic relays K5 andK6. each of which has one end connected to the positive side of powersupply 102. The otherwise free side of electromagnetic relay K5 isslideably and electrically connected to wafer switch 104 by tap member124 at a point adjacent to tap member 118. The otherwise free side ofelectromagnetic relay K6 is likewise connected to wafer switch 104 bytap member 126 which is positioned adjacent tap member 120. Each of theelectromagnetic relays, K5 and K6, have respective contacts K5 and K6which are connected respectively to the forward and reverse sides ofreversible direct current motor 60, reversible direct motor 60 being themotor for controlling the engageable clutch member 30 as described inFIG. 1.' The contacts K5 and K6 connect reversible motor 60 to groundwhen their respective electromagnetic relays are de-energized. This isindicated by a solid line representation of K5 and K6 in FIG. 6. Thedotted line representation of contacts K5 and K6 indicate the positionsof these contacts when their respective electromagnetic relays areenergized and will control reversible motor 60 as described below.

In operation, when the clutch lever is positioned such that engine 18and outboard drive unit 20 are disengaged as described with respect toFIG. 1, switch which is mechanically coupled to clutch lever 70 ispositioned in its N position as seen in FIG. 6. This disconnects bothelectromagnetic relays K5 and K6 from power supply 102. As seen in FIG.6 the wafer switch 104 is positioned such that its nonconductive portion108b is in contact-with tap member 122.

When it is desired to forwardly engage engine 18 and outboard drive unit20 the clutch lever 70 is positioned such that switch 110 is in its Fposition. This closes the circuit through electromagnetic relay K5 suchthat the current from power supply 102 will pass through electromagneticrelay K5 and thereafter to the negative side of the power supply throughtap member 124, conductive portion 106a of wafer switch 104 and tapmember 118, energizing electromagnetic relay K5. This is,

of course, assuming that switches 114 and 116 are closed. These switchesare coupled to throttle lever 68, by means not shown, such that switch114 is closed only when the throttle lever is in its idle position andswitch 116 is energized at the same time so as to close its contact apredetermined period 'of time after the throttle lever has beenpositioned in its idle position. The reason for the time delay is sothat the engine 18 can drop back to its idle speed before actualshifting takes place.

With electromagnetic relay K energized contact K5 is positioned, asindicated in dotted lines so as to connect the forward side ofreversible motor 60 to a 12- volt power supply. This drives reversiblemotor 60 forwardly, as described in FIG. 1, for forwardly engagingengine 18 and outboard drive unit 20. As the motor 60 is forwardlydriven, the motor drives its mechanically connected wafer switch 104 soas to move in a counterclockwise direction as viewed in FIG. 6 untilnonconductive portion 108a encompasses tap members 118 and 124. Thisdisconnects the circuit through electromagnetic relay KS, de-energizingelectromagnetic relay K5 and reversible motor 60.

If it is desired to reversely engage engine 18 and outboard drive unit20, clutch lever 70 is moved such that switch 110 is in its R positionfor energizing electromagnetic relay K6. In such a position, currentfrom power supply 102 passes through electromagnetic relay K6, tapmember 126, conductive portion 106a of wafer switch 104 which is nowpositioned under taps 120 and 126, tap member 120 and ultimately to thenegative side of power supply 102. This again is assuming that throttlelever 68 is positioned such that switches 114 and 116 are closed. Withelectromagnetic relay K6 energized, contact K6 is positioned asindicated in dotted lines such that reversible motor 60 is reverselydriven by the l2-volt power supply for appropriately driving mechanicalclutch member 30 as described with respect to FIG. 1.

As motor 60 is reversely driven, wafer switch 104 is driven clockwise.When nonconductive portion l08b encompasses tap members 120 and 126, thecircuit through electromagnetic relay K6 is again opened deenergizing K6and reversible motor 60. The engine 18 and outboard drive unit 20 arenow reversely engaged.

If it is finally desired to disengage the engine and drive unit, clutchlever 70 is appropriately positioned such that switch 110 is again inits N position so as to energize electromagnetic relay K5. In thissituation the current from power supply 102 passes throughelectromagnetic relay KS, tap member 124, conductive portion 106 ofwafer switch 104 which now is positioned under the tap members 118, 122and 124, tap member 122 and thereafter to the negative side of powersupply 102. This ultimately causes the wafer switch again to be drivencounterclockwise until nonconductive portion 108b is positioned undertap member 122 for disconnecting the switch.

It is to be understood that an electronic control switch circuit similarto that described with respect to FIG. 6 is provided for the clutchcontrols of inboardoutboard drive system 14 and actuated by clutch levera.

While a particular embodiment of the invention has been shown, it shouldbe understood, of course, that the invention is not limited theretosince many modifications may be made, and it is, therefore, contemplatedto cover by the appended claims any such modifications that fall withinthe true spirit and scope of the invention.

The invention is claimed as follows:

1. [n a control system for a boat having engine means, drive means andclutch means for selectively connecting the engine means to the drivemeans, the combination comprising: a clutch actuating motor connected tothe clutch means for moving the same between engaged and disengagedpositions when connecting and disconnecting the engine means and thedrive means, three position switch means selectively actuated toforward, neutral, and reverse positions, rotational switch means havingcontacts coupled between said three position switch means and saidclutch actuating motor to cooperate with said three position switchmeans for running said motor in one direction when said three positionswitch means is in the forward position and for running said motor inthe opposite direction when said three position switch means is in thereverse position, and for running said motor in either said onedirection or said opposite direction when said three position switchmeans is in the neutral position, drive means connected between saidclutch actuating motor and said rotational switch means for rotating thesame to a position where the contacts thereof are disconnected from saidclutch actuating motor to stop the motor selectively at the forward,neutral, and reverse positions, and condition sensing means connected incircuit with said three position switch means to allow enabling of saidclutch actuating motor only when a throttle lever associated with theengine means is in a position to have the engine means running at idlespeed, said condition sensing means including time delay switch means toprovide sufficient time after the throttle has been moved to the idleposition to allow the engine speed to completely return to the idlespeed.

2. In the control system of claim 1 wherein said condition sensing meansincludes switch contacts connected in series with said three positionswitch means.

3. In the control system of claim 1 further including first and secondrelay coils connected to first and second groups of contacts of saidrotational switch means, each of said relay coils having contacts, onerelay contact connected to one end of said clutch actuating motor andthe other relay contact connected to the other end of said clutchactuating motor, whereby energization of one or the other of said relaycoils will cause energization of said clutch actuating motor.

1. In a control system for a boat having engine means, drive means andclutch means for selectively connecting the engine means to the drivemeans, the combination comprising: a clutch actuating motor connected tothe clutch means for moving the same between engaged and disengagedpositions when connecting and disconnecting the engine means and thedrive means, three position switch means selectively actuated toforward, neutral, and reverse positions, rotational switch means havingcontacts coupled between said three position switch means and saidclutch actuating motor to cooperate with said three position switchmeans for running said motor in one direction when said three positionswitch means is in the forward position and for running said motor inthe opposite direction when said three position switch means is in thereverse position, and for running said motor in either said onedirection or said opposite direction when said three position switchmeans is in the neutral position, drive means connected between saidclutch actuating motor and said rotational switch means for rotating thesame to a position where the contacts thereof are disconnected from saidclutch actuating motor to stop the motor selectively at the forward,neutral, and reverse positions, and condition sensing means connected incircuit with said three position switch means to allow enabling of saidclutch actuating motor only when a throttle lever associated with theengine means is in a position to have the engine means running at idlespeed, said condition sensing means including time delay switch means toprovide sufficient time after the throttle has been moved to the idleposition to allow the engine speed to completely return to the idlespeed.
 2. In the control system of claim 1 wherein said conditionsensing means includes switch contacts connected in series with saidthree position switch means.
 3. In the control system of claim 1 furtherincluding first and second relay coils connected to first and secondgroups of contacts of said rotational switch means, each of said relaycoils having contacts, one relay contact connected to one end of saidclutch actuating motor and the other relay contact connected to theother end of said clutch actuating motor, whereby energization of one orthe other of said relay coils will cause energization of said clutchactuating motor.